221001221212100 has 288 divisors, whose sum is σ = 567886602931200. Its totient is φ = 73076767948800.

The previous prime is 221001221212087. The next prime is 221001221212151. The reversal of 221001221212100 is 1212122100122.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 17775367484 + ... + 17775379916.

It is an arithmetic number, because the mean of its divisors is an integer number (1971828482400).

Almost surely, 2^{221001221212100} is an apocalyptic number.

221001221212100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221001221212100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (283943301465600).

221001221212100 is an abundant number, since it is smaller than the sum of its proper divisors (346885381719100).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221001221212100 is a wasteful number, since it uses less digits than its factorization.

221001221212100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19543 (or 19536 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 221001221212100 its reverse (1212122100122), we get a palindrome (222213343312222).

The spelling of 221001221212100 in words is "two hundred twenty-one trillion, one billion, two hundred twenty-one million, two hundred twelve thousand, one hundred".